Quantum chemical investigations of surface chemistry with a hierarchy of cluster models

使用簇模型层次结构对表面化学进行量子化学研究

• 批准号: 0911454
• 负责人: Krishnan Raghavachari
• 金额: $ 45.25万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0911454&HistoricalAwards=false
• 关键词: Quantum; chemical; investigations; surface; chemistry

Krishnan Raghavachari is supported by an award from the Theoretical and Computational Chemistry program to develop theoretical methods for studying surface chemistry by developing and applying a set of hierarchical theoretical models. The hierarchical concept involves the use of highly accurate methodology on small systems to validate more approximate and computationally cost effective methodologies for investigating complex systems. Building on prior work in the PI's research group, Raghavachari and coworkers are developing more sophisticated and broadly applicable methods in three areas: (1) accurate thermochemical models applicable for 3d and 4d transition metal elements and fourth-row main group elements. These methods are based on the successful Gaussian-n (Gn) models, but will include many improvements to overcome known deficiencies; (2) divalent pseudoatom parameters to enable accurate and efficient calculations for investigating chemistry on (100) surfaces of tetrahedrally bonded systems; (3) new electronic embedding methods for an accurate treatment of QM/QM multilayer calculations based on the popular ONIOM framework. These developments are applied to a range of applications on semiconductor and metal-oxide surface chemistry, including (1) controlled functionalization of Si(100) surfaces, (2) alloy growth of compound semiconductor surfaces, (3) reactions of biomolecules on silica surfaces, and (4) catalytic mechanisms of titanium oxide and vanadium oxide surfaces. The computer codes developed in this program are available to the scientific community as part of the Gaussian software package as well as in a set of freely available codes on the PI's website.

Krishnan Raghavachari获得了理论和计算化学计划的奖项，通过开发和应用一套分层理论模型来开发研究表面化学的理论方法。等级概念涉及使用 小型系统上的高精度方法，以验证用于调查复杂系统的更近似和计算成本有效的方法。在PI研究小组先前工作的基础上，Raghavachari及其同事正在三个领域开发更复杂和广泛适用的方法：（1）适用于3d和4d过渡金属元素和第四行主族元素的精确热化学模型。这些方法是基于成功的Gaussian-n（Gn）模型，但将包括许多改进，以克服已知的不足之处;（2）二价假原子参数，使准确和有效的计算，研究化学的（100）表面的四面体键合系统;（3）新的电子嵌入方法的准确处理QM/QM多层计算的基础上流行的ONIOM框架。 这些进展应用于半导体和金属氧化物表面化学的一系列应用，包括（1）Si（100）表面的受控功能化，（2）化合物半导体表面的合金生长，（3）生物分子在二氧化硅表面上的反应，以及（4）氧化钛和氧化钒表面的催化机制。在该计划中开发的计算机代码可作为高斯软件包的一部分提供给科学界，也可在PI网站上免费获得一组代码。